Coated wire cloth



Patented Dec. 25, 1934 UNITED STATES PATENT OFFICE COATED WIRE CLOTH NoDrawing. Application October 19, 1931, Serial No. 569,847. In GermanyAugust 7, 1931 15 Claims.

This invention relates to the preparation of wire cloths or screenswhich are coated with transparent or translucent coatings that close themeshes thereof, and relates more particularly 6 to the imparting ofnon-inflammable or flameproofness to such coated wire cloth.

An object of my invention is to prepare unlnfiammable or substantiallynon-combustible coated wire cloth that may be used for many purposesincluding many for which the ordinary inflammable coated wire cloths arenot suitable. Other objects of my invention will appear from thefollowing detailed description.

There is now on the market wire cloth which is coated with transparentlayers of cellulose derivatives, particularly cellulose acetate, andthis is used for the making of windows or transparent walls of poultryhouses. However, such coated wire cloth has the great disadvantage ofbeing very combustible. If such wire cloth, whose meshes are filled forinstance with a layer of cellulose acetate and triphenyl phosphate whichof itself is not combustible, is ignited at the lower end, the thinmetallic wires glow, the glowing metal ignites the transparent film, andthere soon results a very sooty fiame which is transmitted from below toabove, so that in short time the wire cloth coating is destroyed by theflames.

These defects, which naturally prevent an extensive use of wire clothcoated with cellulose derivative films in the interior buildings,heretofore could not be removed, even if there were incorporated in thecellulose derivative plastics unusually large amounts of camphorsubstitutes known to reduce infiammability, especially the boric acidesters, the phosphoric acid esters, halogen containing organic productsand others. While for example amounts of triphenyl phosphi'ite as low as10 to of the weight of the cellulose acetate are suflicient to impartnoninfiammability or non-combustibility to a layer of cellulose acetatealone or to a layer of a mixture of cellulose acetate and about of acombustible plasticizing agent, ten times this amount of triphenylphosphate is not sufilcient to render such a film non-inflammable whenit is coated onto wire cloth. I

I have now made the surprising discovery that fully unburnable orflame-proof wire cloth can 50 be prepared if there are employed besidesthe above named phosphoric acid esters, still larger amounts, andpreferably above 50% (based on the weight of the cellulose derivative),of halogenated substances, as for example tribrom resorcinol,tetrachlorhydroquinone, tribromhydrin,

etc. as plasticizing agents for the cellulose acetate or other cellulosederivative. In many cases it is sumcient to use these highly halogenatedcompounds alone, but in that case amounts of to about 150% arenecessary, whereby translu- 5 cent or cloudy, layers are mainlyproduced. I have found that materials particularly useful for thispurpose are the plasticizing agents which contain both halogen groupsand phosphoric acid esters, as for example, halogenated tricresyl l0phosphate or triphenyl phosphate, such as triparachlorphenyl phosphate,chlorbromcresyl phosphate, tribromethyl phosphate, trichlorbutylphosphate, etc. These substances with two active components display adisproportionately 15 greater eflect than the above named products andcan be used either alone or in admixture with the same, whereby theproportion is governed particularly in accordance with the more or lesshigh retentive powerof the particular cellulose deriva- 20 tive employedso as to avoid the crystallization or sweating out of the added agents.

Coated wire cloth prepared in accordance with this invention can beemployed not only in the same manner as the prior combustible materials25 for windows or outer walls, but they may also be used for variousother purposes such as for wall covers, inter-walls, doors, closets,partitions, protective walls and the like in the interior of buildings.On account of this; it is not always neces-, 30 sary, in fact frequentlynot even desirable, that these be transparent as glass, since in manycases mixtures may be added, which produce only translucent or whitishlayers,'or even opaque filling materials or pigmentsmay be added to the35 film-forming material.

The above described coated wire cloth can be prepared in any desiredmanner by dipping the wire cloth into or by coating the same with asolution of the layer forming material or by 4 laminating the wire clothwith finished layers or films of the material or in other ways.

While this invention is particularly applicable to the preparation ofwire cloth whose meshes are filled with plastics containing celluloseacetate, 45'

the cellulose acetate may be replaced in whole or in part by otherorganic derivatives of cellulose, such as cellulose formate, cellulosepropionate, cellulose butyrate, methyl cellulose, ethyl cellu- 5 lose orbenzyl cellulme.

Instead of cellulose derivatives there may be used similar actingmaterials, particularly synthetic resins, condensation products ofphenol, urea, albumin, etc. with formaldehyde, polymerized vinylcompounds and other transparent filmforming bodies.

The foregoing detailed description is given merely by way ofillustration and many variations may be made therein without departingfrom the spirit of my invention.

Having described my invention, what I desire to secure by Letters Patentis:

1. A composition of matter containing organic derivatives of celluloseand at least one halogenated aliphatic phosphoric ester selected fromthe group consisting of tribromethyl phosphate; trichlorbutyl phosphate.

2. A composition 01 matter containing organic esters of cellulose and atleast one halogenated aliphatic phosphoric ester selected from the groupconsisting of tribromethyl phosphate and trichlorbutyl phosphate.

3. A composition of matter containing cellulose acetate and at least onehalogenated aliphatic phosphoric ester selected from the groupconsisting of tribromethyl phosphate and trichlorbutyl phosphate.

4. A composition of matter containing organic derivatives of celluloseand tribromethyl phosphate.

5. A composition of matter containing cellulose acetate and tribromethylphosphate.

6. A composition of matter containing organic derivatives of celluloseand trichlorbutyl phosphate. I

7. A composition of matter containing cellulose of a compositioncomprising an organic derivative of cellulose and a relatively largeamount of halogenated aliphatic phosphoric ester selected from the groupconsisting of tribromethyl phosphate and thichlorbutyl phosphate asplasticizer for the organic derivative of cellulose, whereby theinflammability or combustibility of the layer forming material, which isincreased by contact with the metal wire, is substantially eliminated.

10. Flame-proof coated metal wire cloth having the meshes thereof closedwith a film-like layer of a composition comprising cellulose acetate anda relatively large amount of a halogenated aliphatic phosphoric esterselected from the group consisting of tribromethyl phosphate andtrichlorbutyl phosphate as plasticizer for the cellulose acetate,whereby the inflammability or combustibility of the layer formingmaterial, which is increased by contact with the metal wire, issubstantially eliminated.

11. Flame-proof coated metal wire cloth having the meshes thereof closedwith a film-like layer of a composition comprising a synthetic resin anda relatively large amount of a halogenated aliphatic phosphoric esterselected from the group consisting of tribromethyl phosphate andtrichlorbutyl phosphate as plasticizer for the synthetic resin, wherebythe inflammability or combustibility of the layer forming material,which is increased by contact with the metal wire, is substantiallyeliminated.

12. Flame-proof coated metal wire cloth having the meshes thereof closedwith a film-like layer of a composition comprising an organic derivativeof cellulose and a relatively large amount of tribromethyl phosphate asplasticizer for the organic derivative of cellulose, whereby theinflammability or combustibility of the layer forming material, which isincreased by contact with the metal wire, is substantially eliminated.

13. Flame-proof coated metal wire cloth having the meshes thereof closedwith a film-like layer of a composition comprising cellulose acetate anda relatively large amount of tribromethyl phosphate as plasticizer forthe cellulose acetate, whereby the inflammability or combustibility ofthe layer forming material, which is increased by contact with the metalwire, is substantially eliminated.

l4. Flame-proof coated metal wire cloth having the meshes thereof closedwith a film-like layer of a composition comprising an organic derivativeof cellulose and a relatively large amount of trichlorbutyl phosphate asplasticizer for the organic derivative of cellulose, whereby theinflammability or combustibility of the layer forming material, which isincreased by contact with the metal wire, is substantially eliminated.

15. Flame-proof coated metal wire cloth having the meshesthereof closedwith a film-like layer of a composition comprising cellulose acetate anda relatively large amount of trichlorbutyl phosphate as plasticizer forthe cellulose acetate, whereby the inflammability or combustibility o!the layer forming material, which is increased by contact with the metalwire, is substantially eliminated.

ARTHUR monuments.

